Metal-dependent ribbon and self-penetrated topologies in nitroaromatic-sensing zinc and cadmium coordination polymers with terephthalate and dipyridylamide ligands

Abstract

Hydrothermal reaction of the requisite metal nitrate, potassium terephthalate (K2tere) and the dipyridylamide 3-pyridylisonicotinamide (3-pina) afforded a pair of crystalline coordination polymers whose dimensionality and topology depends critically on the metal coordination environment. The two new crystalline phases were structurally characterized via single-crystal X-ray diffraction. {[Zn(tere)(3-pina)2]·2H2O}n (1) manifests a 1-D zig-zag ribbon motif with monodentate 3-pina ligands. [Cd(tere)(3-pina)2]n (2) displays a self-penetrated 3-D network with 446108 mab topology. Thermal and luminescent properties of these two new materials are also presented. Both 1 and 2 show capability as sensors for nitroaromatic compounds via luminescence quenching, with better absorption for nitrobenzene than the more sterically bulky analyte m-nitrophenol.